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The potential of enriched Pb (

Lead exposure can cause substantial organ damage. Enteral lead absorption may be reduced by concomitant intake of clinoptilolite tuff, a zeolite from natural sources. This study aimed to assess the effect of purified clinoptilolite tuff (G-PUR) on enteral lead uptake in adults using stable lead isotope 204Pb as a tracer. In this randomized, placebo-controlled, double-blind, parallel-group study, 42 healthy participants were randomized to receive oral G-PUR 2.0 g, 2 * 2.0 g, or placebo, together with 2.5 µg of 204Pb in water. The enrichment of 204Pb caused by the tracer in blood and urine was measured by mass spectrometry. G-PUR was well tolerated. The mean maximum 204Pb enrichment of 0.505% of total blood lead was significantly higher (p 204Pb AUC0-192 was 86.5, 11.9, and 8.5% * h without and with G-PUR 2.0 g, and G-PUR 2 * 2.0 g, respectively (p 204Pb exposure was paralleled by a reduced urinary excretion in subjects receiving G-PUR. Concomitant oral intake of purified clinoptilolite tuff reduced enteral uptake of 204Pb in healthy humans by approximately 90%. The reduced bioavailability is demonstrable by a decrease of 204Pb tracer enrichment in blood and urine.Trial registration: clinicaltrials.gov identifier: NCT04138693, registered 24/10/2019.

A versatile approach to determining the elemental content of more than 50 elements in different components of electronic devices on the example of smartphones was developed. The analytical protocol is based on accurate disassembly of smartphones, a single processing microwave-assisted acid digestion followed by ICP-OES and ICP-MS measurements. Method optimization and validation were performed using the certified reference material ERM®-EZ505 electronic scrap. Combined uncertainties revealed measurement uncertainty and sample heterogeneity as main contributors. The contents of up to 57 elements could be quantified in the certified reference material ERM®-EZ505 electronic scrap. The results of the certified elements Au, Be, Cu, In, Ni, Pd, and Pt overlapped within their uncertainties with the certified range and revealed recoveries of 100% ± 16%. Only Ag shows incomplete recoveries (75% ± 35%). The validated method was applied to all metal-containing components of selected smartphones, excluding batteries. The contents of up to 57 elements could be quantified and are presented exemplarily for printed circuit boards, which represent the most complex components in the investigated smartphones and thus limit the capability of the method. The ten most abundant elements in decreasing order are Cu, Fe, Si, Ni, Sn, Zn, Ba, Al, Cr, Ti, which comprise approx. 80% of the weight of the printed circuit boards. The method allows for the determination of metal content in various parts of modern smartphones, providing the basis for the estimation and prediction of future metal usage and thus the comprehensive investigation of recycling and circular economy aspects.

53 metallic elements from smartphones were investigated with regard to metal prices, metal production, and content in comparison to mined ores. The metal content of the 7.42 billion smartphone devices sold from 2012 to 2017 could theoretically maintain the global supply for 91 days for Ga, 73 days for Ta, 23 days for Pd, 14 days for Au, and 6 days for REE. The pure metal value of a single smartphone device for the investigated metals currently sums to 1.13 US $; it averaged at 1.05 US $ from 2012 to 2017 with the highest value of 1.32 US $ in 2012. The Au content is low (16.83 mg per device), yet constitutes the highest value with a current share of approximately 72% of total value for all measured metals, followed by Pd (10%). Approximately 82% of total metal value can be recycled with current standard recycling methods for Au, Cu, Pd, Pt, which only comprise 6 wt% of the total device. The printed circuit board (pcb) contains 90% of the measured Au, 98% of Cu, 99% of Pd, 86% of In, and 93% of Ta. The Au, Pd, Cu, Pt, Ta, In, Ga contents in a smartphone pcb are significantly higher than the metal content in currently mined ores. Magnets contain 96% of the measured REE and 40% of the measured Ga, with higher concentrations than ores for REE and Ga. For Co and Ge, metal content in smartphones (w/o batteries) is lower than in ores.

The commercial use of Tetragonula biroi Friese pot-pollens is strongly limited due to scarce data about its properties and composition. Eight pollen samples of T. biroi Friese, indigenous stingless bees from Philippines, were analysed for physicochemical properties and chemical composition. The average chemical main composition showed a relatively narrow range among all samples. Most of determined values met the proposed general quality criteria for bee pollen. The samples contained fructose (4.39 – 9.58 g/100 g), glucose (0.25 – 1.95 g/100 g), sucrose (4.29 – 26.04 g/100 g) and small amounts of di- and trisaccharides; besides sucrose, mannitol (12.66 ± 5.47 g/100 g on average) was highest in concentration among all analysed carbohydrates and sugar alcohols. Furthermore, moderate amounts of soluble proteins and free amino acids were found. The predominant fatty acids were palmitic, α-linolenic and linoleic acids. The major elements quantified were calcium and magnesium. Our results revealed the high nutritive value of T. biroi pollen. The values obtained from this study may serve as basis for standardization of physicochemical requirements and quality parameters for bee pollen from T. biroi.